Spectral Analysis of Gravity Data of NW Himalaya

The Bouguer anomaly and topography across the NW Himalaya are analyzed by different spectral methods. The power spectrum of Bouguer anomaly is calculated to derive the mean depth of the interfaces. The spectral analysis suggests three layer interfaces in the lithosphere at 68, 34 and 11 km mean depths corresponding to the Moho, the Conrad discontinuity and the Himalayan décollement thrust, respectively. The coherence function is calculated and interpreted to derive the effective elastic thickness (EET) and configuration of relative folding of the crustal layers. The admittance and cross spectra are calculated and correlated to understand the folding of the layers and the presence of a decoupling zone.